```html
<!DOCTYPE html>
<html lang="zh-CN">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>算法图解：有效字母异位词</title>
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        body {
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            background-color: #f8f9fa;
            color: #333;
            line-height: 1.6;
        }
        .hero {
            background: linear-gradient(135deg, #6e8efb 0%, #a777e3 100%);
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            transform: translateY(-5px);
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            background: linear-gradient(135deg, #6e8efb 0%, #a777e3 100%);
            color: white;
            margin-right: 1rem;
        }
    </style>
</head>
<body class="min-h-screen">
    <!-- Hero Section -->
    <section class="hero text-white py-20 px-4 md:px-0">
        <div class="container mx-auto max-w-4xl text-center">
            <h1 class="text-4xl md:text-5xl font-bold mb-6">有效字母异位词</h1>
            <p class="text-xl md:text-2xl font-light mb-8">探索字符串背后的算法奥秘</p>
            <div class="flex justify-center">
                <div class="inline-flex items-center bg-white bg-opacity-20 rounded-full px-6 py-3">
                    <i class="fas fa-lightbulb mr-2"></i>
                    <span>一种优雅的字符串比较方法</span>
                </div>
            </div>
        </div>
    </section>

    <!-- Main Content -->
    <main class="container mx-auto max-w-4xl px-4 md:px-0 py-12">
        <!-- Problem Section -->
        <section class="mb-16">
            <div class="flex items-center mb-8">
                <div class="concept-icon">
                    <i class="fas fa-question-circle text-2xl"></i>
                </div>
                <h2 class="text-3xl font-bold">题目描述</h2>
            </div>
            <div class="bg-white rounded-xl shadow-md p-8 card-hover transition-all duration-300">
                <p class="text-xl leading-relaxed">
                    <span class="first-letter">给</span>定两个字符串 s 和 t，判断它们是否是字母异位词。字母异位词指字母相同但排列不同的字符串。
                </p>
                <div class="mt-6 p-4 bg-blue-50 rounded-lg border-l-4 border-blue-500">
                    <div class="flex items-start">
                        <div class="flex-shrink-0">
                            <i class="fas fa-info-circle text-blue-500 mt-1"></i>
                        </div>
                        <div class="ml-3">
                            <p class="text-blue-700">例如，"anagram"和"nagaram"是字母异位词，而"rat"和"car"则不是。</p>
                        </div>
                    </div>
                </div>
            </div>
        </section>

        <!-- Visualization Section -->
        <section class="mb-16">
            <div class="flex items-center mb-8">
                <div class="concept-icon">
                    <i class="fas fa-project-diagram text-2xl"></i>
                </div>
                <h2 class="text-3xl font-bold">概念图解</h2>
            </div>
            <div class="visualization p-6 mb-8">
                <div class="mermaid">
                    graph TD
                        A[字母异位词] --> B[相同字符]
                        A --> C[不同顺序]
                        B --> D[字符频率相同]
                        C --> E[排序后相等]
                </div>
            </div>
            <div class="grid md:grid-cols-2 gap-6">
                <div class="bg-white p-6 rounded-xl shadow-md card-hover transition-all duration-300">
                    <div class="flex items-center mb-4">
                        <div class="w-10 h-10 rounded-full bg-purple-100 flex items-center justify-center mr-3">
                            <i class="fas fa-sort-alpha-down text-purple-600"></i>
                        </div>
                        <h3 class="text-xl font-semibold">排序法</h3>
                    </div>
                    <p class="text-gray-700">将两个字符串排序后直接比较，如果相同则是字母异位词。</p>
                </div>
                <div class="bg-white p-6 rounded-xl shadow-md card-hover transition-all duration-300">
                    <div class="flex items-center mb-4">
                        <div class="w-10 h-10 rounded-full bg-blue-100 flex items-center justify-center mr-3">
                            <i class="fas fa-table text-blue-600"></i>
                        </div>
                        <h3 class="text-xl font-semibold">哈希表法</h3>
                    </div>
                    <p class="text-gray-700">使用哈希表统计字符出现频率，比较频率是否一致。</p>
                </div>
            </div>
        </section>

        <!-- Solution Section -->
        <section class="mb-16">
            <div class="flex items-center mb-8">
                <div class="concept-icon">
                    <i class="fas fa-code text-2xl"></i>
                </div>
                <h2 class="text-3xl font-bold">解决方案</h2>
            </div>
            <div class="bg-white rounded-xl shadow-md overflow-hidden card-hover transition-all duration-300">
                <div class="bg-gray-800 px-6 py-4 flex items-center">
                    <div class="w-3 h-3 rounded-full bg-red-500 mr-2"></div>
                    <div class="w-3 h-3 rounded-full bg-yellow-500 mr-2"></div>
                    <div class="w-3 h-3 rounded-full bg-green-500 mr-2"></div>
                    <span class="text-gray-300 ml-2">Python</span>
                </div>
                <div class="p-6">
                    <pre class="code-block p-4 rounded-lg overflow-x-auto"><code class="language-python">def isAnagram(s, t):
    if len(s) != len(t):
        return False
    counter = [0] * 26
    for c1, c2 in zip(s, t):
        counter[ord(c1) - ord('a')] += 1
        counter[ord(c2) - ord('a')] -= 1
    return all(x == 0 for x in counter)</code></pre>
                </div>
            </div>
        </section>

        <!-- Analysis Section -->
        <section>
            <div class="flex items-center mb-8">
                <div class="concept-icon">
                    <i class="fas fa-chart-line text-2xl"></i>
                </div>
                <h2 class="text-3xl font-bold">算法分析</h2>
            </div>
            <div class="bg-white rounded-xl shadow-md p-8 card-hover transition-all duration-300">
                <div class="grid md:grid-cols-2 gap-8">
                    <div>
                        <h3 class="text-xl font-semibold mb-4">时间复杂度</h3>
                        <div class="flex items-center mb-3">
                            <div class="w-8 h-8 rounded-full bg-green-100 flex items-center justify-center mr-3">
                                <i class="fas fa-clock text-green-600"></i>
                            </div>
                            <div>
                                <p class="font-medium">O(n)</p>
                                <p class="text-gray-600 text-sm">线性时间复杂度</p>
                            </div>
                        </div>
                        <p class="text-gray-700">我们只需要遍历字符串一次，因此时间复杂度为O(n)，其中n是字符串的长度。</p>
                    </div>
                    <div>
                        <h3 class="text-xl font-semibold mb-4">空间复杂度</h3>
                        <div class="flex items-center mb-3">
                            <div class="w-8 h-8 rounded-full bg-blue-100 flex items-center justify-center mr-3">
                                <i class="fas fa-memory text-blue-600"></i>
                            </div>
                            <div>
                                <p class="font-medium">O(1)</p>
                                <p class="text-gray-600 text-sm">常数空间复杂度</p>
                            </div>
                        </div>
                        <p class="text-gray-700">我们只使用了固定大小的计数器数组(26位)，所以空间复杂度是O(1)。</p>
                    </div>
                </div>
            </div>
        </section>
    </main>

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        // 添加微交互效果
        document.querySelectorAll('.card-hover').forEach(card => {
            card.addEventListener('mouseenter', () => {
                card.classList.add('shadow-lg');
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</body>
</html>
```